The Islamist organization which has overrun large areas of Iraq and Syria declared itself an Islamic caliphate and proclaimed its leader Abu Bakr al-Baghdadi “imam and Khalifa for Muslims everywhere,” ISIS spokesman Muhammad al-Adnani said in a statement Sunday night. The caliphate would stretch from Iraq’s eastern province of Diyala (on the Iranian border) to Syria’s Aleppo, according to the statement posted on Islamist websites and Twitter in several languages.